Light-emitting device with reflective layer

ABSTRACT

A light-emitting device includes a semiconductor structure including a first semiconductor layer, a second semiconductor layer on the first semiconductor layer, and an active layer between the first semiconductor layer and the second semiconductor layer, wherein the second semiconductor layer includes a first edge; a reflective structure located on the second semiconductor layer and including an outer edge; a first electrode pad located on the reflective structure, wherein the first electrode pad including an outer side wall adjacent to the outer edge, wherein the outer edge extends beyond the outer side wall and does not exceed the first edge in a cross-sectional view of the light-emitting device.

REFERENCE TO RELATED APPLICATION

This application is a continuation application of U.S. patentapplication Ser. No. 17/165,290, filed on Feb. 2, 2021, which is acontinuation application of U.S. patent application Ser. No. 16/877,840,filed on May 19, 2020, which is a continuation application of U.S.patent application Ser. No. 16/416,488, filed on May 20, 2019, which isa continuation application of U.S. patent application Ser. No.15/874,398, filed on Jan. 18, 2018, which claims priority of U.S.Provisional Application No. 62/450,860 filed on Jan. 26, 2017 under 35U.S.C. § 119(e), the entire content of which is hereby incorporated byreference.

TECHNICAL FIELD

The application relates to a structure of a light-emitting device, andmore particularly, to a light-emitting device including a semiconductorstack and a reflective layer on the semiconductor stack.

DESCRIPTION OF BACKGROUND ART

Light-Emitting Diode (LED) is a solid-state semiconductor light-emittingdevice, which has the advantages of low power consumption, low heatgeneration, long working lifetime, shockproof, small volume, fastreaction speed and good photoelectric property, such as stable emissionwavelength. Therefore, light-emitting diodes are widely used inhousehold appliances, equipment indicators, and optoelectronic products.

SUMMARY OF THE APPLICATION

A light-emitting device includes a semiconductor structure including afirst semiconductor layer, a second semiconductor layer on the firstsemiconductor layer, and an active layer between the first semiconductorlayer and the second semiconductor layer, wherein the secondsemiconductor layer includes a first edge; a reflective structurelocated on the second semiconductor layer and including an outer edge; afirst electrode pad located on the reflective structure, wherein thefirst electrode pad including an outer side wall adjacent to the outeredge, wherein the outer edge extends beyond the outer side wall and doesnot exceed the first edge in a cross-sectional view of thelight-emitting device.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a top view of a light-emitting device 1 c inaccordance with an embodiment of the present application.

FIG. 2 illustrates a cross-sectional view of the light-emitting device 1c taken along line D-D′ of FIG. 1 in accordance with an embodiment ofthe present application.

FIGS. 3A-3C respectively illustrate a partial cross-sectional view of atransparent conductive layer and a reflective layer of a light-emittingdevice in accordance with embodiments of the present application.

FIG. 3D illustrates a partial cross-sectional view of a light-emittingdevice in accordance with an embodiment of the present application.

FIG. 4A illustrates a table listing characteristics of samples A˜B.

FIG. 4B illustrates a table listing characteristics of samples C˜F.

FIG. 5 illustrates a top view of a light-emitting device 2 c inaccordance with an embodiment of the present application.

FIGS. 6A-6I illustrate process flows of the light-emitting devices 1 c,2 c in accordance with the embodiments of the present application.

FIG. 7 illustrates a cross-sectional view of the light-emitting device 2c taken along line E-E′ of FIG. 5 in accordance with an embodiment ofthe present application.

FIG. 8 illustrates a schematic view of a light-emitting apparatus 3 inaccordance with an embodiment of the present application; and

FIG. 9 illustrates a structure diagram of a light-emitting apparatus 4in accordance with an embodiment of the present application.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

The embodiment of the application is illustrated in detail, and isplotted in the drawings. The same or the similar part is illustrated inthe drawings and the specification with the same or the similar number.

FIG. 1 illustrates a top view of the light-emitting device 1 c inaccordance with an embodiment of the present application. FIG. 2 is across-sectional view of the light-emitting device 1 c taken along lineD-D′ of FIG. 1 . FIGS. 6A,6B, 6C, 6D, 6E, 6G-6I, illustrate process flowof the light-emitting device 1 c in accordance with the embodiment ofthe present application. The light-emitting device 1 c disclosed in thepresent embodiment is a flip chip light-emitting diode. Thelight-emitting device 1 c includes a substrate 11 c and one or moresemiconductor structures 1000 c on the substrate 11 c. Each of the oneor more semiconductor structures 1000 c includes a semiconductor stack10 c including a first semiconductor layer 101 c, a second semiconductorlayer 102 c, and an active layer 103 c between the first semiconductorlayer 101 c and the second semiconductor layer 102 c. The active layer103 c and the second semiconductor layer 102 c orderly stack on thefirst semiconductor layer 101 c along a stacking direction. Thesemiconductor structure 1000 c includes an exposed part exposing a partof the first semiconductor layer 101 c. As shown in FIG. 2 and FIG. 6A,parts of the second semiconductor layer 102 c and the active layer 103 care removed to expose the exposed part including a first surface 1011 cand one or more second surface 1012 c of the first semiconductor layer101 c. In one embodiment, the first surface 1011 c is at an outerperiphery of the one or more semiconductor structures 1000 c. The firstsurface 1011 c surrounds the second semiconductor layer 102 c and theactive layer 103 c remaining on the substrate 11 c. FIG. 6A illustratesa top view of the semiconductor structures 1000 c. In the presentembodiment, the light-emitting device 1 c includes only onesemiconductor structure 1000 c and the first surface 1011 c of the firstsemiconductor layer 101 c surrounds the second semiconductor layer 102 cand the active layer 103 c. Besides, in the present embodiment, thefirst surface 1011 c is substantially located at a periphery region ofthe semiconductor structure 1000 c. In other embodiment, thelight-emitting device 1 c further includes an exposed surface 11 s ofthe substrate 11 c to surround the outer periphery of the semiconductorstructure 1000 c. The light-emitting device 1 c further includes one ormore openings, such as vias 100 c passing through the secondsemiconductor layer 102 c and the active layer 103 c to expose one ormore second surfaces 1012 c of the first semiconductor layer 101 c. Inone embodiment, the multiple semiconductor structures 1000 c areseparated by the one or more openings, such as trenches, and connectedto each other by the first semiconductor layer 101 c. In one embodiment(not shown), the multiple semiconductor structures 1000 c are physicallyseparated by the one or more openings without the first semiconductorlayer 101 c connecting. In one embodiment, the light-emitting device 1 cfurther includes a first insulating structure 20 c, a transparentconductive layer 30 c, a reflective structure including a reflectivelayer 40 c or a barrier layer 41 c, a second insulating structure 50 c,a contact layer 60 c, a third insulating structure 70 c, a first pad 80c and a second pad 90 c on the one or more semiconductor structures 1000c.

In an embodiment of the present application, the substrate 11 c includesa patterned surface. The patterned surface includes a plurality ofprojections. A shape of the projection includes taper or cone. Theprojection can enhance the light-extraction efficiency of thelight-emitting device. In an embodiment of the present application, thesubstrate 11 c can be a growth substrate, such as gallium arsenide(GaAs) wafer for growing aluminum gallium indium phosphide (AlGaInP),sapphire (Al₂O₃) wafer, gallium nitride (GaN) wafer or silicon carbide(SiC) wafer for growing gallium nitride (GaN) or indium gallium nitride(InGaN). The semiconductor stack 10 c can be formed of group III nitridebased compound semiconductor on the substrate 11 c by metal organicchemical vapor deposition (MOCVD), molecular beam epitaxy (MBE),physical vapor deposition (PVD), hydride vapor deposition (HVPE), or ionplating, such as sputtering or evaporation. Moreover, a buffer structure(not shown) can be formed before forming the semiconductor stack 10 c soas to relieve lattice mismatch between the substrate 11 c and thesemiconductor stack 10 c and can be formed of a GaN-based materiallayer, such as gallium nitride or aluminum gallium nitride, or anAlN-based material layer, such as aluminum nitride. The buffer structurecan be a single layer or multiple layers. The buffer structure can beformed by metal organic chemical vapor deposition (MOCVD), molecularbeam epitaxy (MBE) or physical vapor deposition (PVD). The PVD methodincludes a sputtering method, for example, reactive sputtering method orevaporation method, such as e-beam evaporation method or thermalevaporation method. In one embodiment, the buffer structure includes anAlN buffer layer and is formed by the sputtering method. The AlN bufferlayer is formed on a growth substrate with a patterned surface. Thesputtering method can produce a dense buffer layer with high uniformity,and therefore the AlN buffer layer can conformably deposit on thepatterned surface of the substrate 11 c.

In an embodiment of the present application, the semiconductor stack 10c includes optical characteristics, such as light-emitting angle orwavelength distribution, and electrical characteristics, such as forwardvoltage or reverse current. In an embodiment of the present application,the first semiconductor layer 101 c and the second semiconductor layer102 c, such as a cladding layer or a confinement layer, have differentconductivity types, electrical properties, polarities, or dopingelements for providing electrons or holes. For example, the firstsemiconductor layer 101 c is an n-type semiconductor, and the secondsemiconductor layer 102 c is a p-type semiconductor. The active layer103 c is formed between the first semiconductor layer 101 c and thesecond semiconductor layer 102 c. The electrons and holes combine in theactive layer 103 c under a current driving to convert electric energyinto light energy and then light is emitted from the active layer 103 c.The wavelength of the light emitted from the light-emitting device 1 cis adjusted by changing the physical and chemical composition of one ormore layers in the semiconductor stack 10 c. The material of thesemiconductor stack 10 c includes a group III-V semiconductor material,such as Al_(x)In_(y)Ga_((1-x-y))N or Al_(x)In_(y)Ga_((1-x-y))P, wherein0≤x, y≤1, and (x+y)≤1. According to the material of the active layer 103c, when the material of the semiconductor stack 10 c is AlInGaP seriesmaterial, red light having a wavelength between 610 nm and 650 nm oryellow light having a wavelength between 550 nm and 570 nm can beemitted. When the material of the semiconductor stack 10 c is InGaNseries material, blue or deep blue light having a wavelength between 400nm and 490 nm or green light having a wavelength between 490 nm and 550nm can be emitted. When the material of the semiconductor stack 10 c isAlGaN series material, UV light having a wavelength between 400 nm and250 nm can be emitted. The active layer 103 c can be a singleheterostructure (SH), a double heterostructure (DH), a double-sidedouble heterostructure (DDH), or a multi-quantum well structure (MQW).The material of the active layer 103 c can be i-type, p-type, or n-typesemiconductor.

Referring to FIG. 2 , in an embodiment, the semiconductor structures1000 c includes a first outside wall 1003 c and a second outside wall1001 c, wherein one end of the first surface 1011 c of the firstsemiconductor layer 101 c connects the first outside wall 1003 c andanother end of the first surface 1011 c connects the second outside wall1001 c. The second outside wall 1001 c includes the side-surfaces of thefirst semiconductor layer 101 c, the active layer 103 c and the secondsemiconductor layer 102 c. In the present embodiment, the second outsidewall 1001 c is composed by the side-surfaces of the first semiconductorlayer 101 c, the active layer 103 c and the second semiconductor layer102 c. The first outside wall 1003 c locates between the first surface1011 c and the substrate 11 c. In one embodiment, the first outside wall1003 c and the second outside wall 1001 c are inclined to the firstsurface 1011 c of the first semiconductor layer 101 c. In oneembodiment, the first outside wall 1003 c is inclined to the exposedsurface 11 s of the substrate 11 c. An angle between the first outsidewall 1003 c and the exposed surface 11 s is an acute angle. In oneembodiment, an angle between the first outside wall 1003 c and theexposed surface 11 s is an obtuse angle.

The semiconductor stack 10 c further includes an inside wall 1002 c.Similar to the second outside wall 1001 c, the inside wall 1002 c iscomposed by side-surfaces of the first semiconductor layer 101 c, theactive layer 103 c and the second semiconductor layer 102 c at the via100 c. In an embodiment of the present application, the via 100 c isdefined by the inside wall 1002 c and the second surfaces 1012 c of thefirst semiconductor layer 101 c. One end of the inside wall 1002 c isconnected to the second surface 1012 c of the first semiconductor layer101 c and another end of the inside wall 1002 c is connected to asurface 102 s of the second semiconductor layer 102 c. The surface 102 sof the second semiconductor layer 102 c is substantially perpendicularto the stacking direction. The inside wall 1002 c and the second outsidewall 1001 c are inclined to the surface 102 s of the secondsemiconductor layer 102 c, and the inside wall 1002 c is also inclinedto the second surface 1012 c of the first semiconductor layer 101 c. Anangle between the inside wall 1002 c and the second surface 1012 c is anacute angle or an obtuse angle, and an angle between the second outsidewall 1001 c and the first surface 1011 c is an acute angle or an obtuseangle. The angle between the second outside wall 1001 c and the surface102 s is about 100 degrees˜140 degrees, similar to the angle between theinside wall 1002 c and the surface 102 s. Besides, the semiconductorstructures 1000 c further includes a first edge E1, which is anintersection of the second outside wall 1001 c and the surface 102 s ofthe second semiconductor layer 102 c, and a second edge E2, which is aninterconnection of the inside wall 1002 c and the surface 102 s of thesecond semiconductor layer 102 c. In a top view, the secondsemiconductor layer 102 includes the first edge E1. More specifically,the first edge E1 is a contour of the surface 102 s of the secondsemiconductor layer 102, and the second edge E2 is a contour of the via100 c in the top view of the light-emitting device 1 c. In oneembodiment, the first edge E1 or the second edge E2 is closed. In oneembodiment, the second edge E2 is surrounded by the first edge E1.

FIG. 6B illustrates a top view of the first insulating structure 20 c.In an embodiment of the present application, the first insulatingstructure 20 c of the light-emitting device 1 c is formed on thesemiconductor structure 1000 c by sputtering or vapor deposition. Asshown in FIGS. 2 and 6B, the first insulating structure 20 c includes asurrounding insulating part 201 c and a plurality of ring-shaped caps202 c in a top view. In the present embodiment, the surroundinginsulating part 201 c is disposed on an area of the semiconductorstructure 1000 c around the first edge E1 and the plurality ofring-shaped caps 202 c is disposed on an area of the semiconductorstructure 1000 c around the second edge E2. In one embodiment, both ofthe surrounding insulating part 201 c and the plurality of ring-shapedcaps 202 c covers a portion of the surface 102 s of the secondsemiconductor layer 102 c, the second outside wall 1001 c, the insidewall 1002 c of the semiconductor structure 1000 c. Besides, thesurrounding insulating part 201 c covers a portion of the first surface1011 c, and the ring-shaped caps 202 c covers a portion of the secondsurface 1012 c. As shown in FIG. 2, the first insulating structure 20 cincludes a top portion f20 c on the surface 102 s of the secondsemiconductor layer 102 c, a side portion s20 c disposed on the secondoutside wall 1001 c and the inside wall 1002 c, and a bottom portion t20c on the first surface 1011 c and the second surface 1012 c of the firstsemiconductor layer 101 c. The bottom portion t20 c exposes parts of thesecond surface 1012 c and the first surface 1011 c. More specifically,the first insulating structure 20 c is formed on the first surface 1011c, the second surface 1012 c, the second outside wall 1001 c, the insidewall 1002 c and the surface 102 s. The first insulating structure 20 cfurther includes an opening 203 c on the surface 102 s of the secondsemiconductor layer 102 c defined by a side surface of the top portionf20 c. The first insulating structure 20 c further includes anotheropening 204 c, on the second surface 1012 c, and defined by a sidesurface of the bottom portion t20 c. The material of the firstinsulating structure 20 c includes a non-conductive material. Thenon-conductive material includes organic material, inorganic material,or dielectric material. The organic material includes Sub,benzocyclobutene (BCB), perfluorocyclobutane (PFCB), epoxy resin,acrylic resin, cyclic olefin polymers (COC), polymethylmethacrylate(PMMA), polyethylene terephthalate (PET), polycarbonate (PC),polyetherimide, or fluorocarbon polymer. The inorganic material includessilicone, or glass. The dielectric material includes aluminum oxide(Al₂O₃), silicon nitride (SiN_(x)), silicon oxide (SiO_(x)), titaniumoxide (TiO_(x)), or magnesium fluoride (MgF_(x)). In one embodiment, thefirst insulating structure 20 c includes one layer or multiple layers.The first insulating structure 20 c protects the sidewalls of thesemiconductor stack 10 c to prevent the active layer 103 c from beingdestroyed by the following processes. When the first insulatingstructure 20 c includes multiple layers, the first insulating structure20 c can be a distributed Bragg reflector (DBR). The DBR can protectsthe sidewalls of the semiconductor stack 10 c, and can furtherselectively reflect light of a specific wavelength emitted from theactive layer 103 c to outside of the light-emitting device 1 c toenhance brightness. Specifically, the first insulating structure 20 ccan be formed by alternately stacking two sub-layers, such as a SiO_(x)sub-layer and a TiO_(x) sub-layer. More specifically, the DBR couldinclude a plurality pairs of sub-layers, and each sub-layer has arefractive index different from that of adjacent sub-layers. The DBRprovides a high reflectivity for particular wavelength or within aparticular wavelength range by setting the refractive index differencebetween the sub-layer with a high refractive index and the sub-layerwith a low refractive index in each pair respectively. The thicknessesof two sub-layers in each pair can be different. Besides, thethicknesses of the sub-layers in the DBR with the same material can bethe same or different.

FIG. 6C illustrates a top view of the transparent conductive layer 30 c.As shown in FIGS. 1, 2, and 6C, in the present embodiment, thetransparent conductive layer 30 c of the light-emitting device 1 c isformed on the surface 102 s of the second semiconductor layer 102 c. Inone embodiment, the transparent conductive layer 30 c can further coversa part of the top portion f20 c of the first insulating structure 20 c.More specifically, the transparent conductive layer 30 c includes afirst outer edge 301 c and a first inner edge 302 c locates on thesurface 102 s of the second semiconductor layer 102 c. The transparentconductive layer 30 c doesn't extend beyond the first edge E1 and thesecond edge E2. That is, the first outer edge 301 c is closer to acenter of the semiconductor structure 1000 c than the first edge E1 is,and the first inner edge 302 c is closer to the center of thesemiconductor structure 1000 c than the second edge E2 is in a top viewof the light-emitting device 1 c as shown in FIG. 1 . The first outeredge 301 c is surrounded by the first edge E1 and the first inner edge302 c surrounds the second edge E2 in the top view of the light-emittingdevice 1 c. In one embodiment, the transparent conductive layer 30 c cancover the side portion s20 c of the first insulating structure 20 c.

The quality of the first insulating structure 20 c might be affected bythe process ability or stress. Some cracks might be produced in thefirst insulating structure 20 c. In one embodiment, the transparentconductive layer 30 c is located on the surface 102 s and devoid ofextending to cover the second outside wall 1001 c and the inside wall1002 c to reduce a risk that short current occurs between thetransparent conductive layer 30 c and the semiconductor stack 10 ccaused by current leakage from the cracks of the first insulatingstructure 20 c. Therefore, the reliability of the light-emitting device1 c can be consistent. Since the transparent conductive layer 30 c issubstantially formed on entire of the surface 102 s of the secondsemiconductor layer 102 c and contacts the second semiconductor layer102 c, the current can be uniformly spread throughout entire the secondsemiconductor layer 102 c by the transparent conductive layer 30 c.

The material of the transparent conductive layer 30 c includes amaterial being transparent to the light emitted from the active layer103 c, such as metal oxide. The metal oxide includes indium tin oxide(ITO), indium zinc oxide (IZO), indium oxide (InO), tin oxide (SnO),cadmium tin oxide (CTO), antimony tin oxide (ATO), aluminum zinc oxide(AZO), zinc tin oxide (ZTO), gallium doped zinc oxide (GZO), tungstendoped indium oxide (IWO) or zinc oxide (ZnO). The transparent conductivelayer 30 c can be configured to form a low-resistance contact, forexample, ohmic contact, with the second semiconductor layer 102 c. Thetransparent conductive layer 30 c includes a single layer or multiplelayers. For example, as the transparent conductive layer 30 c includesmultiple sub-layers, the transparent conductive layer 30 c can be adistributed Bragg reflector (DBR). In the embodiment, the DBR of thetransparent conductive layer 30 c is electrically conductive. In oneembodiment, in a top view, a shape of the transparent conductive layer30 c substantially corresponds to a shape of the second semiconductorlayer 102 c. Please refer to FIGS. 6A and 6C, the shape of thetransparent conductive layer 30 c shown in FIG. 6C substantiallycorresponds to the shape of the second semiconductor layer 102 c shownin FIG. 6A.

In an embodiment of the present application, the reflective structure ofthe light-emitting device 1 c is formed on the transparent conductivelayer 30 c. The reflective structure includes the reflective layer 40 c,the barrier layer 41 c or a combination of the above. In one embodiment,in a top view, a shape of the reflective layer 40 c substantiallycorresponds to a shape of the second semiconductor layer 102 c. FIG. 6Dillustrates a top view of the reflective layer 40 c. As shown in FIGS.1, 2, and 6D, the reflective layer 40 c includes a second outer edge 401c and a second inner edge 402 c. In the embodiment, the reflective layer40 c neither outwardly extends to exceed the first outer edge 301 cand/or the first inner edge 302 c of the transparent conductive layer 30c nor outwardly extends to exceed the first edge E1 and/or the secondedge E2 of the semiconductor structure 1000 c. The first outer edge 301c of the transparent conductive layer 30 c is disposed between thesecond outer edge 401 c of the reflective layer 40 c and the first edgeE1, and/or the first inner edge 302 c is disposed between the secondinner edge 402 c and the second edge E2. In other words, the first outeredge 301 c is closer to the first edge E1 than the second outer edge 401c to the first edge E1, and the first inner edge 302 c is closer to thesecond edge E2 than the second inner edge 402 c to the second edge E2.In one embodiment, the reflective layer 40 c covers a part of the topportion f20 c of the first insulating structure 20 c, such as the topportion f20 c on the surface 102 s, and the reflective layer 40 c isdevoid of covering the side portion s20 c and the bottom portion t20 c.Beside, a part of the transparent conductive layer 30 c near the firstedge E1 and/or the second edge E2 is located between the reflectivelayer 40 c and the top portion f20 c. Specifically, the second outeredge 401 c and/or the second inner edge 402 c are devoid of extending toexcess the first outer edge 301 c and/or the first inner edge 302 crespectively. In one embodiment, the transparent conductive layer 30 ccan avoid peeling issue between the reflective layer 40 c and the firstinsulating structure 20 c. More specifically, the reflective layer 40 cconnects to the first insulating structure 20 c via the transparentconductive layer 30 c, and the transparent conductive layer 30 cdisposed between them can increase the adhesion between the reflectivelayer 40 c and the first insulating structure 20 c.

In one embodiment, the second outer edge 401 c is aligned to the firstouter edge 301 c of the transparent conductive layer 30 c, and/or thesecond inner edge 402 c is aligned to the first inner edge 302 c of thetransparent conductive layer 30 c. In one embodiment, the second outeredge 401 c is misaligned with the first edge E1 and/or the second inneredge 402 c is misaligned with the second edge E2.

In one embodiment, neither the reflective layer 40 c nor the transparentconductive layer 30 c extends to cover the side walls, such as thesecond outside wall 1001 c and the inside wall 1002 c, of thesemiconductor structure 1000 c to reduce an electrical short risk in thelight-emitting device 1 c that is caused by current leakage through thereflective layer 40 c, the transparent conductive layer 30 c, and thecracks of the first insulating structure 20 c to the semiconductorstructure 1000 c. More specifically, since the second outside wall 1001c and the inside wall 1002 c are composed by the side-surfaces of thefirst semiconductor layer 101 c, the active layer 103 c and the secondsemiconductor layer 102 c, if the reflective layer 40 c extends to thesecond outside wall 1001 c and the inside wall 1002 c may cause currentleakage when the first insulating structure 20 c having defects orcracks. More specifically, some of metal material of the reflectivelayer 40 c (such as silver, aluminum) may diffuse to the firstsemiconductor layer 101 c and the second semiconductor layer 102 cthrough the defects or cracks of the first insulating structure 20 c,and therefore a short current is caused due to the electrical connectionbetween the first semiconductor layer 101 c and the second semiconductorlayer 102 c via the diffusion of the reflective layer 40 c. Therefore,the reliability of the light-emitting device 1 c would be decreased whenthe reflective layer 40 c excesses the first edge E1 and the second edgeE2 and covers the side portion s20 c. However, the application will notbe limited by the embodiments. Other producing methods, material of thefirst insulating structure 20 c or structures of the first insulatingstructure 20 c such as multiple-insulating layers can be used to improvethe quality, mechanical strength of the first insulating structure 20 cto prevent the current short issue.

In one embodiment, from the top view of the light-emitting device 1 c,the second semiconductor layer 102 c includes a first area, and thereflective layer 40 c includes a second area. In the embodiment, fromthe top view of the light-emitting device 1 c, the first area is definedby the first edge E1 and the second edge E2 of the second semiconductorlayer 102 c, and the second area is defined by the second outer edge 401c and the second inner edge 402 c of the reflective layer 40 c. Thefirst edge E1 of the second semiconductor layer 102 c surrounds thesecond outer edge 401 c of the reflective layer 40 c, and the secondinner edge 402 c surrounds the second edge E2 of the secondsemiconductor layer 102 c. In order to enhance the brightness of thelight-emitting device 1 c, the more light emitted from the active layer103 c can be reflected by the reflective layer 40 c, the more brightnesscan be enhanced. So the second area of the reflective layer 40 c shouldbe designed as large as possible. A tradeoff between the brightness andthe reliability of the light-emitting device 1 c has to be considered.In one embodiment, the second area of the reflective layer 40 c is notless than 80% of the first area of the second semiconductor layer 102 c.In one embodiment, the second area is 82%-96% of the first area. In oneembodiment, the second area is 85%-95% of the first area.

In other embodiment, a distance D is between the second outer edge 401 cof the reflective layer 40 c and the first edge E1 of the semiconductorstructure 1000 c. A distance D′ is between the second inner edge 402 cand the second edge E2. In one embodiment, the distance D or thedistance D′ is greater than zero. In one embodiment, the distance D orthe distance D′ is not greater than 10 μm. In one embodiment, thedistance D or the distance D′ is not greater than 8 μm. In theembodiment, the distances D, D′ are greater than 0 μm and less than 10μm. In one embodiment, the distances D, D′ are between 2 μm and 8 μm.Furthermore, in other embodiment, the distance D and distance D′ couldbe the same or different.

In one embodiment, the barrier layer 41 c is formed on and covers thereflective layer 40 c. An outer edge (not shown) of the barrier layer 41c surrounds the second outer edge 401 c of the reflective layer 40 c,and/or an inner edge (not shown) of the barrier layer 41 c surrounds thesecond inner edge 402 c of the reflective layer 40 c. In one embodiment,the reflective layer 40 c is formed on and covers the barrier layer 41c. The outer edge of the barrier layer 41 c can be surrounded by thesecond outer edge 401 c of the reflective layer 40 c, and/or the inneredge of the barrier layer 41 c can be surrounded by the second inneredge 402 c of the reflective layer 40 c. In one embodiment, the outeredge and the inner edge of the barrier layer 41 respectively overlap oralign with the second outer edge 401 c and the second inner edge 402 cof the reflective layer 40 c.

FIGS. 3A-3C respectively illustrate a partial cross-sectional view ofthe transparent conductive layer 30 c and the reflective layer 40 c nearthe first edge E1 or the second edge E2 of the light-emitting device 1 cin accordance with embodiments of the present application. Thereflective layer 40 c is formed on the transparent conductive layer 30c. In one embodiment, as shown in FIG. 3A, the reflective layer 40 c andthe transparent conductive layer 30 c are formed on the first insulatingstructure 20 c and devoid of extending onto the sidewalls or into thevia 100 c of the semiconductor structure 1000 c. In one embodiment, asshown in FIGS. 3B-3C, the reflective layer 40 c and the transparentconductive layer 30 c which are formed on the first insulating structure20 c, extend onto the sidewalls or into the via 100 c of thesemiconductor structure 1000 c.

In one embodiment, as shown in FIG. 3A, the reflective layer 40 c is adiscontinuous structure and includes a first reflective portion 403 cand a second reflective portion 404 c separated from the firstreflective portion 403 c. There is a gap G between the first reflectiveportion 403 c and the second reflective portion 404 c. In oneembodiment, as shown in FIG. 3A, the transparent conductive layer 30 cis a discontinuous structure and includes a first conductive portion 31c and a second conductive portion 32 c separated from the firstconductive portion 31 c. The second conductive portion 32 c and thesecond reflective portion 404 c are entirely disposed on the firstinsulating structure 20 c and the second semiconductor layer 102 c. Inone embodiment, the first conductive portion 31 c and the secondconductive portion 32 c locate under the first reflective portion 403 cand the second reflective portion 404 c respectively. Since the firstreflective portion 403 c disconnects with the second reflective portion404 c and the first conductive portion 31 c disconnects with the secondconductive portion 32 c, and the second conductive portion 32 c and thesecond reflective portion 404 c are entirely disposed on the firstinsulating structure 20 c, the current is unable to flow between thefirst reflective portion 403 c and the second reflective portion 404 c.That is, the second reflective portion 404 c electrically disconnects tothe first reflective portion 403 c.

In the embodiment shown in FIG. 3B, the differences between theembodiment in FIG. 3B and the embodiment in FIG. 3A are the transparentconductive layer 30 c includes a first conductive portion 31 c and athird conductive portion 33 c separated from the first conductiveportion 31 c, and the reflective layer 40 c includes a first reflectiveportion 403 c and a third reflective portion 405 c separated from thefirst reflective portion 403 c in FIG. 3B. There is a gap G between thefirst reflective portion 403 c and the third reflective portion 405 c.Therefore, the third reflective portion 405 c, and the first reflectiveportion 403 c are electrically insulated from each other. Morespecifically, the third conductive portion 33 c is formed on the firstinsulating structure 20 c and the second semiconductor layer 102 c, andextends onto the second outside wall 1001 c to cover the side portions20 c and the bottom portion t20 c of the first insulating structure 20c. In one embodiment, the third conductive portion 33 c is formed on thefirst insulating structure 20 c and the second semiconductor layer 102c, and extends onto the inside wall 1002 c to cover the side portion s20c of the first insulating structure 20 c. The first reflective portion403 c and the third reflective portion 405 c are formed on the firstconductive portion 31 c and the third conductive portion 33 crespectively.

In one embodiment, as shown in FIG. 3C, the reflective layer 40 cincludes a first reflective portion 403 c′, a second reflective portion404 c′ and a third reflective portion 405 c′ separated from one another.Besides, the transparent conductive layer 30 c includes a firstconductive portion 31 c′, the second conductive portion 32 c′ and athird conductive portion 33 c′ separated from one another. Therefore,the third reflective portion 405 c′, the second reflective portion 404c′ and the first reflective portion 403 c′ are electrically insulatedfrom one another. In individual light-emitting devices in accordancewith the embodiments shown in FIGS. 3A-3C, each of the reflective layers40 c is the discontinuous structure and electrically disconnected, thecurrent leakage can be avoided while the reflective layer 40 c extendsonto the sidewalls of the semiconductor structure 1000 c to increase thesecond area of the reflective layer 40 c. Both of the reflective areafor brightness and the reliability of the individual light-emittingdevices have been considered. In one embodiment, the light-emittingdevices shown in FIGS. 3A-3C, the second area of the reflective layer 40c is not less than 80% of the first area of the second semiconductorlayer 102 c, and the distance D between the first edge E1 and the secondouter edge 401 c is between 0 μm and 10 μm. In one embodiment, the firstouter edge 301 c and the second outer edge 401 c are closer to thecenter of the semiconductor structure 1000 c than the first edge E1 inthe light-emitting device shown in FIG. 3A. The first edge E1 is closerto the center of the semiconductor structure 1000 c than the first outeredge 301 c and the second outer edge 401 c in FIGS. 3B-3C. Since thereflective layer 40 c covers the sidewalls of the semiconductorstructure 1000 c in FIGS. 3B-3C, the second areas of the reflectivelayer 40 c of the light-emitting device shown in FIGS. 3B-3C are largerthan that shown in FIG. 3A. Besides, the second area of the reflectivelayer 40 c shown in FIG. 3C could be larger than that shown in FIG. 3Aor FIG. 3B, and thus the brightness of the light-emitting device shownin FIG. 3C can be higher than that of the light-emitting device shown inFIG. 3A or FIG. 3B.

In an embodiment of the present application, the reflective layer 40 cincludes multiple sub-layers, such as a Distributed Bragg reflector(DBR). In the embodiment, the material of the DBR can be electricallyisolated or electrically conductive.

In an embodiment of the present application, the reflective layer 40 cincludes a single layer structure or a multi-layer structure, and thematerial of the reflective layer 40 c includes a metal material with ahigh reflectance for the light emitted by the active layer 103 c, suchas silver (Ag), gold (Au), aluminum (Al), titanium (Ti), chromium (Cr),copper (Cu), nickel (Ni), platinum (Pt) or an alloy thereof. The highreflectance referred to herein means having 80% or more reflectance fora wavelength of a light emitted from the active layer 103 c.

In an embodiment of the present application, the reflective structurefurther includes a DBR structure below the reflective layer 40 c. In oneembodiment, the DBR structure is formed between the semiconductorstructure 1000 c and the reflective layer 40 c. A connecting layer canbe chosen to insert between the DBR structure and the reflective layer40 c to increase the adhesion between them. For example, in the DBRstructure, a first layer is connected to the reflective layer 40 c,wherein the first layer includes silicon oxide (SiO₂) and the reflectivelayer 40 c includes silver (Ag). The connecting layer therebetweenincludes ITO, IZO or the other similar material has higher adhesion tothe reflective layer 40 c than the first layer of the DBR structure has.

In an embodiment of the present application, the reflective structurefurther includes the barrier layer 41 c, which covers the reflectivelayer 40 c to prevent the surface of the reflective layer 40 c frombeing oxidized that deteriorates the reflectivity of the reflectivelayer 40 c. The material of the barrier layer 41 c includes metalmaterial, such as titanium (Ti), tungsten (W), aluminum (Al), indium(In), tin (Sn), nickel (Ni), platinum (Pt), zinc (Zn), chromium (Cr) oran alloy of the above materials. The barrier layer 41 c can include asingle layer structure or a multi-layer structure. When the barrierlayer 41 c is the multi-layer structure, the barrier layer 41 c isalternately stacked by a first barrier layer (not shown) and a secondbarrier layer (not shown), for example, Cr/Pt, Cr/Ti, Cr/TiW, Cr/W,Cr/Zn, Ti/Pt, Ti/W, Ti/TiW, Ti/W, Ti/Zn, Pt/TiW, Pt/W, Pt/Zn, TiW/W,TiW/Zn, or W/Zn. In one embodiment, the material of the barrier layer 41c includes a metal material other than gold (Au) or copper (Cu).

In an embodiment of the present application, the second insulatingstructure 50 c of the light-emitting device 1 c is formed on thesemiconductor structure 1000 c by sputtering or vapor deposition. Thesecond insulating structure 50 c is formed on the semiconductorstructure 1000 c, the first insulating structure 20 c, the transparentconductive layer 30 c and the reflective layer 40 c. FIG. 6E.illustrates a top view of the second insulating structure 50 c. As shownin FIGS. 1, 2, and 6E, the second insulating structure 50 c includes oneor multiple first insulating openings 501 c to expose the second surface1012 c of the first semiconductor layer 101 c, and one or multiplesecond insulating openings 502 c to expose the reflective layer 40 c orthe barrier layer 41 c. In an embodiment, the first insulating openings501 c and the second insulating openings 502 c include different widthsor numbers. From the top view of the light-emitting device 1 c, theshapes of the first insulating openings 501 c and the second insulatingopenings 502 c include circular, elliptical, rectangular, polygonal, orarbitrary shapes. In one embodiment, the positions of the firstinsulating openings 501 c are formed to correspond to the positions ofthe vias 100 c. In the embodiment, the one second insulating openings502 c is at one side of the light-emitting device 1 c opposite to thefirst insulating openings 501 c.

The second insulating structure 50 c is formed of a non-conductivematerial and includes organic material, inorganic material or dielectricmaterial. The organic material includes Sub, benzocyclobutene (BCB),perfluorocyclobutane (PFCB), epoxy resin, acrylic resin, cyclic olefinpolymers (COC), polymethylmethacrylate (PMMA), polyethyleneterephthalate (PET), polycarbonate (PC), polyetherimide, or fluorocarbonpolymer. The inorganic material includes silicone, or glass. Thedielectric material includes aluminum oxide (Al₂O₃), silicon nitride(SiN_(x)), silicon oxide (SiO_(x)), titanium oxide (TiO_(x)), ormagnesium fluoride (MgF_(x)). In one embodiment, the second insulatingstructure 50 c includes one layer or multiple layers. In one embodiment,the second insulating structure 50 c can be a distributed Braggreflector (DBR). Specifically, the second insulating structure 50 c canbe formed by alternately stacking a SiO_(x) sub-layer and a TiO_(x)sub-layer. The material of the second insulating structure 50 c and thatof the first insulating structure 20 c can be the same or different.

FIG. 6G. illustrates a top view of the contact layer 60 c. As shown inFIGS. 1, 2, and 6G, in one embodiment, the contact layer 60 c is formedon the second insulating structure 50 c and the reflective layer 40 c oron the barrier layer 41 c. The contact layer 60 c includes a firstcontact part 601 c, a second contact part 602 c, and a pin region 600 celectrically separated from one another. Herein, the first contact part601 c is electrically connected to the first semiconductor layer 101 c,the second contact part 602 c is electrically connected to the secondsemiconductor layer 102 c and the pin region 600 c is electricallyisolated from the first contact part 601 c and the second contact part602 c. The first contact part 601 c is formed on the first surface 1011c of the first semiconductor layer 101 c to surround a periphery of thesemiconductor structure 1000 c and contact the first semiconductor layer101 c to form an electrical connection. In one embodiment, first contactpart 601 c includes a peripheral length larger than a peripheral lengthof the active layer 103 c. In one embodiment, the first contact part 601c is also formed on the second surfaces 1012 c of the firstsemiconductor layer 101 c to cover the one or multiple vias 100 c viathe plurality of first insulating openings 501 c of the secondinsulating structure 50 c and contact the first semiconductor layer 101c to form an electrical connection. The pin region 600 c is deposited onthe second semiconductor layer 102 c, and electrically isolated from thefirst semiconductor layer 101 c and the second semiconductor layer 102 cby the second insulating structure 50 c. In the present embodiment, thepin region 600 c is substantially deposited at the center of thelight-emitting device 1 c from the top-view. Additionally, the secondcontact part 602 c electrically connects the surface 102 s of the secondsemiconductor layer 102 c via the reflective layer 40 c and thetransparent conductive layer 30 c to form an electrical connectionbetween the second contact part 602 c and the second semiconductor layer102 c. In the present embodiment, from the top-view of thelight-emitting device 1 c, the pin region 600 c is located between thefirst contact part 601 c and the second contact part 602 c. The pinregion 600 c and the second contact part 602 c are surrounded by thefirst contact part 601 c as shown in FIG. 6G. In one embodiment, the pinregion 600 c is electrically connected to one of the first contact part601 c or the second contact part 602 c. A shape of the pin region 600 cin a top-view includes a geometric shape, for example, a rectangle or acircle. The contact layer 60 c can be a single layer structure or amulti-layer structure. The material of the contact layer 60 c includesmetal such as aluminum (Al), silver (Ag), chromium (Cr), platinum (Pt),nickel (Ni), titanium (Ti), tungsten (W), or zinc (Zn).

After the contact layer 60 c is formed, a third insulating structure 70c is disposed on the contact layer 60 c and covers the contact layer 60c. FIG. 6H. illustrates a top view of the third insulating structure 70c. As shown in FIGS. 1, 2, and 6H, the third insulating structure 70 cincludes a first opening 701 c and a second opening 702 c. The firstopening 701 c exposes the first contact part 601 c of the contact layer60 c, and the second opening 702 c exposes the second contact part 602 cof the contact layer 60 c. The third insulating structure 70 c includesone layer or multiple layers. When the third insulating structure 70 cincludes multiple layers, the third insulating structure 70 c can form aDistributed Bragg reflector (DBR). A material of the third insulatingstructure 70 c includes non-conductive material which includes organicmaterials, inorganic materials or dielectric material. The organicmaterial includes Sub, benzocyclobutene (BCB), perfluorocyclobutane(PFCB), epoxy resin, acrylic resin, cyclic olefin polymers (COC),polymethylmethacrylate (PMMA), polyethylene terephthalate (PET),polycarbonate (PC), polyetherimide, or fluorocarbon polymer. Theinorganic material includes silicone, or glass. The dielectric materialincludes aluminum oxide (Al₂O₃), silicon nitride (SiN_(x)), siliconoxide (SiO_(x)), titanium oxide (TiO_(x)), or magnesium fluoride(MgF_(x)). The first insulating structure 20 c, the second insulatingstructure 50 c, and the third insulating structure 70 c can be the samematerial or different materials selected from the materials describedabove. The first insulating structure 20 c, the second insulatingstructure 50 c, and the third insulating structure 70 c can be formed byprinting, evaporation or sputtering.

After the third insulating structure 70 c is formed, the first pad 80 cand the second pad 90 c are formed on the semiconductor stack 10 c. FIG.6I. illustrates a top view of the first pad 80 c and the second pad 90c. As shown in FIGS. 1, 2, and 6I, the positions and/or shapes of thefirst pad 80 c and the second pad 90 c also respectively correspond tothose of the first opening 701 c and the second opening 702 c of thethird insulating structure 70 c. The first pad 80 c is electricallyconnected to the first semiconductor layer 101 c through the firstopening 701 c of the third insulating structure 70 c and the firstcontact part 601 c of the contact layer 60 c, and the second pad 90 c iselectrically connected to the second semiconductor layer 102 c throughthe second opening 702 c of the third insulating structure 70 c, thesecond contact part 602 c of the contact layer 60 c, the reflectivelayer 40 c and the transparent conductive layer 30 c. In the top view ofthe light-emitting device 1 c, the first pad 80 c includes the sameshape as that of the second pad 90 c, for example, the first pad 80 cand the second pad 90 c include rectangular shape, but the presentdisclosure is not limited hereto. In other embodiment, the shape or thesize of the first pad 80 c can be different from that of the second pad90 c for recognizing the first pad 80 c and the second pad 90 c or forproducing a good current spreading in the light-emitting device 1 c. Forexample, the shape of the first pad 80 c can be rectangular, and theshape of the second pad 90 c is comb-shaped, and the area of the firstpad 80 c is larger than that of the second pad 90 c. In the embodiment,the first pad 80 c and the second pad 90 c includes a structure havingone or more layers. Materials of the first pad 80 c and the second pad90 c include metal materials, such as chromium (Cr), titanium (Ti),tungsten (W), aluminum (Al), indium (In), tin (Sn), nickel (Ni),platinum (Pt), or an alloy of the above materials. When the first pad 80c and the second pad 90 c include a multi-layer structure, the first pad80 c and the second pad 90 c includes an upper pad and a lower pad (notshown) respectively. The upper pad and the lower pad have differentfunctions. The function of the upper pad is used for soldering orwiring. The light-emitting device 1 c can be flipped and mounted on apackage substrate (not shown) by using solder bonding or AuSn eutecticbonding through the upper pad. The metal material of the upper padincludes highly ductile materials such as nickel (Ni), cobalt (Co), iron(Fe), titanium (Ti), copper (Cu), gold (Au), tungsten (W), zirconium(Zr), molybdenum (Mo), tantalum (Ta), aluminum (Al), silver (Ag),platinum (Pt), palladium (Pd), rhodium (Rh), iridium (Ir), ruthenium(Ru) or osmium (Os). The upper pad can be a single layer, or amultilayer film of the above materials. In an embodiment of the presentapplication, the material of the upper pad preferably includes nickel(Ni) and/or gold (Au), or an alloy thereof. The function of the lowerpad is for forming a stable interface with the contact layer 60 c, thereflective layer 40 c, or the barrier layer 41 c, for example, improvingthe interface bonding strength between the lower pad and the contactlayer 60 c, or enhancing the interface bonding strength between thelower pad of the second pad 90 c and the reflective layer 40 c or thebarrier layer 41 c. Another function of the lower pad is to preventmaterial of the solder, such as tin (Sn), or AuSn from diffusing intothe reflective structure and damaging the reflectivity of the reflectivestructure. Therefore, the lower pad can include metal materialsdifferent from the upper pad. That is, the material of the lower padinclude the material other than gold (Au) and copper (Cu), such asnickel (Ni), cobalt (Co), iron (Fe), titanium (Ti), tungsten (W),zirconium (Zr), molybdenum (Mo), tantalum (Ta), aluminum (Al), silver(Ag), platinum (Pt), palladium (Pd), rhodium (Rh), iridium (Ir),ruthenium (Ru), osmium (Os). The lower pad can be a single layer, analloy, or a multilayer film of the above materials. In an embodiment ofthe present application, the lower pad preferably includes a multilayerfilm of titanium (Ti) and aluminum (Al), or a multilayer film ofchromium (Cr) and aluminum (Al).

FIGS. 6A, 6B′, 6C-6D, 6E′, 6G-6I, illustrate process flow of thelight-emitting device in accordance with another embodiment of thepresent application. The main differences between the light-emittingdevice in the present embodiment and the light-emitting device 1 c arethe structures of the first insulating structure 20 c and the secondinsulating structure 50 c. Please refer to FIG. 6B′, the firstinsulating structure 20 c includes a surrounding insulating part 201 cand a plurality of ring-shaped caps 202 c. Herein, the surroundinginsulating part 201 c includes a plurality of protrusions 2011 c and aplurality of recesses 2012 c. In the embodiment, the plurality ofprotrusions 2011 c and the plurality of recesses 2012 c of thesurrounding insulating part 201 c are alternately arranged. FIG. 3Dillustrates a partial cross-sectional view at one of the protrusions2011 c of the light-emitting device in accordance with the presentembodiment. As shown in FIGS. 3D and 6B′, the surrounding insulatingpart 201 c is disposed along the first surface 1011 c and surrounds thesemiconductor structure 1000 c. In the embodiment, the plurality ofprotrusions 2011 c and the plurality of recesses 2012 c of thesurrounding insulating part 201 c are alternately arranged on the firstsurface 1011 c. Specifically, the plurality of protrusions 2011 cextends from the surface 102 s of the second semiconductor layer 102 cand covers portions of the first surface 1011 c of the semiconductorstructure 1000 c, and the plurality of recesses 2012 c exposes otherportions of the first surface 1011 c. In other words, the first surface1011 c includes a first exposed area exposed by the surroundinginsulating part 201 c, and the first exposed area is discontinuous.

Please refer to FIG. 6E′, the second insulating structure 50 c includesa periphery 503 c including a plurality of protrusions 5031 c and aplurality of recesses 5032 c in the present embodiment. As shown in FIG.3D, the second insulating structure 50 c covers the first insulatingstructure 20 c, so that the second outside wall 1001 c and a portion ofthe first surface 1011 c which is covered by the first insulatingstructure 20 c are also covered by the second insulating structure 50 c.Additionally, the plurality of protrusions 5031 c and the plurality ofrecesses 5032 c of the second insulating structure 50 c are arrangedalternately along the first surface 1011 c of the semiconductorstructure 1000 c. Moreover, in the embodiment, a shape of the periphery503 c of second insulating structure 50 c corresponds to a shape of aperiphery of the first insulating structure 20 c for discontinuouslyexposing the first surface 1011 c of the semiconductor structure 1000 c.More specifically, shapes and positions of the plurality of protrusions5031 c and the plurality of recesses 5032 c respectively correspond toshapes and positions of the plurality of protrusions 2011 c and theplurality of recesses 2012 c of the surrounding insulating part 201 c.In such manner, the first surface 1011 c exposed by the plurality ofrecesses 2012 c of the first insulating structure 20 c can be alsoexposed by the plurality of recesses 5032 c of the second insulatingstructure 50 c. The first surface 1011 c covered by the plurality ofprotrusions 2011 c can be covered by the plurality of protrusions 5031c. In other words, the first surface 1011 c includes a second exposedarea exposed by the plurality of recesses 5032 c, and the second exposedarea is discontinuous. The second exposed area of the first surface 1011c substantially corresponds to the first exposed area exposed by thefirst insulating structure 20 c. Please refer to FIG. 6G, in theembodiment, the first contact part 601 c is electrically connected tothe first semiconductor layer 101 c by contacting the first surface 1011c via the plurality of recesses 5032 c of the second insulatingstructure 50 c and the plurality of recesses 2012 c of the firstinsulating structure 20 c. In other words, the first contact part 601 cincludes a discontinuous contact region (not shown) contact the firstsurface 1011 c. In the embodiment, the discontinuous contact regionbetween the first contact part 601 c and the first surface 1011 c of thesemiconductor structure 1000 c benefits current spreading of thelight-emitting device and avoid breakdown of the light-emitting device.Please refer to FIG. 4A. FIG. 4A shows a table listing thecharacteristics of samples A˜B. More specifically, the table shows thecharacteristics of a conventional light-emitting device (sample A) andthe light-emitting device 1 c in one embodiment of the presentapplication (sample B). Sample A and sample B include the same shape,which is square, and the same chip size, which is 35×35 mil². Thedifferences are the area of the reflective layer of the conventionallight-emitting device is smaller than the reflective layer 40 c of thelight-emitting device 1 c. On the other hand, in the conventionallight-emitting device, the distance between the first edge of the secondsemiconductor layer and the second outer edge of the reflective layer is15 μm. The distance D of the light-emitting device 1 c in the embodimentis 6 μm. The distance D of the light-emitting device 1 c is smaller thanthe distance of the conventional light-emitting device. In other words,the area of the reflective layer 40 c of the light-emitting device 1 cis larger than that of the reflective layer of the conventionallight-emitting device. A ratio of the area of the reflective layer 40 cto the area of the second semiconductor layer 102 c of thelight-emitting device 1 c is larger than a ratio of the area of thereflective layer to the area of the second semiconductor layer of theconventional light-emitting device. The table indicates that, the power(I_(V2)) of the light-emitting device 1 c is enhanced by 1.8% (Δ I_(V2))compared with that of the conventional light-emitting device, while theforward voltage (V_(f2)) and the wavelength (W_(d2)) are kept at thesame levels. Therefore, the reflective layer 40 c with a larger area canenhance the performance of the light-emitting device 1 c.

Please refer to FIG. 4B. FIG. 4B shows a table listing thecharacteristics of samples C˜F. More specifically, the table shows theperformances of the samples C˜F. Sample C is a conventionallight-emitting device. Sample D is a light-emitting device with thecontact layer 60 c including the discontinuous contact region as shownin FIGS. 6B′ 6E′ and 3D but without a larger second area of thereflective layer 40 c as shown in FIGS. 1-2 . Sample E is thelight-emitting device 1 c with a larger second area of the reflectivelayer 40 c as shown in FIGS. 1-2 . Sample F is the light-emitting deviceincluding the contact layer 60 c with the discontinuous contact regionshown in FIGS. 6B′, 6E′ and 3D, and the reflective layer 40 c with thelarger second area as shown in FIGS. 1-2 , which combined the designedfeatures in sample D and sample E. Both of sample D and sample E havemore advanced performance in the brightness compared with sample C.Moreover, the light-emitting device, sample F, has a highest power(Iva).

FIG. 5 illustrates a top view of a light-emitting device 2 c inaccordance with an embodiment of the present application. FIG. 7 is across-sectional view of the light-emitting device 2 c taken along lineE-E ‘of FIG. 5 . FIGS. 6A-6B, 6C’, 6D, 6E-6I respectively show thelayouts of the semiconductor structure 1000 c with the exposed firstsurface 1011 c and the second surface 1012 c of first semiconductorlayer 101 c, the first insulating structure 20 c, the transparentconductive layer 30 c, the reflective layer 40 c, the second insulatingstructure 50 c, an adhesion layer 51 c, the contact layer 60 c, thethird insulating structure 70 c and the pads 80 c, 90 c of thelight-emitting device 2 c. The light-emitting device 2 c in theembodiment is similar to the light-emitting device 1 c shown in FIGS.1-2 . The difference is the light-emitting device 2 c further includesthe adhesion layer 51 c between the second insulating structure 50 c andthe contact layer 60 c. Besides, the transparent conductive layer 30 cof the light-emitting device 2 c further includes a first transparentconductive portion f30 c, a second transparent conductive portion s30 cand a third transparent conductive portion t30 c separated from oneanother different from the transparent conductive layer 30 c of thelight-emitting device 1 c. In one embodiment, the material of the secondinsulating structure 50 c includes silicon oxide (SiO₂) and the materialof the contact layer 60 c includes silver (Ag), the adhesion layer 51 cbetween the second insulating structure 50 c and the contact layer 60 ccan enhance the adhesion between the second insulating structure 50 cand the contact layer 60 c. The adhesion layer 51 c can prevent thecontact layer 60 c peeling from the second insulating structure 50 c.Inserting the adhesion layer 51 c therebetween benefits the reliabilityof the light-emitting device 2 c. The adhesion layer 51 c includes amaterial which has higher adhesion with the second insulating structure50 c than that between the contact layer 60 c and the second insulatingstructure 50 c. The material of the adhesion layer 51 c can betransparent conductive material or metal. The transparent conductivematerial includes metal oxide. The metal oxide includes indium tin oxide(ITO), indium zinc oxide (IZO), indium oxide (InO), tin oxide (SnO),cadmium tin oxide (CTO), antimony tin oxide (ATO), aluminum zinc oxide(AZO), zinc tin oxide (ZTO), gallium doped zinc oxide (GZO), tungstendoped indium oxide (IWO) or zinc oxide (ZnO). The metal includes Pt.However, the material of the adhesion layer 51 c is not limited to theabove material. In one embodiment, a shape and an area of the adhesionlayer 51 c shown in FIG. 6F is similar to that of the second insulatingstructure 50 c shown in FIG. 6E. More specifically, the adhesion layer51 c includes one or multiple first adhesion openings 511 ccorresponding to the first insulating openings 501 c and one or multiplesecond adhesion openings 512 c corresponding to the second insulatingopenings 502 c. In one embodiment, a periphery 513 c of the adhesionlayer 51 c surrounds a periphery 503 c of the second insulatingstructure 50 c for electrically connecting to the first surface 1011 cof the first semiconductor layer 101 c. In the embodiment, the adhesionlayer 51 c extends onto the exposed part of the semiconductor structure1000 c. More specifically, the adhesion layer 51 c extends onto thefirst surface 1011 c and/or the second surface 1012 c as shown in FIG. 7.

Please refer to FIG. 6C′ and FIG. 7 , in the embodiment, the firsttransparent conductive portion f30 c is located on the surface 102 s ofthe second semiconductor layer 102 c, the second transparent conductiveportion s30 c is located on the first surface 1011 c of the exposedpart, and the third transparent conductive portion t30 c is located onthe second surface 1012 c of the exposed part in the via 100 c. Thetransparent conductive layer 30 c connects to the adhesion layer 51 c onthe exposed part. The third transparent conductive portion t30 c issurrounded by the first transparent conductive portion f30 c, and thefirst transparent conductive portion f30 c is surrounded by the secondtransparent conductive portion s30 c in a top view of the transparentconductive layer 30 c as shown in FIG. 6C′. The area of the firsttransparent conductive portion f30 c is larger than the secondtransparent conductive portion s30 c and the third transparentconductive portion t30 c. More specifically, the first transparentconductive portion f30 c includes a first periphery f30 c 1, the secondtransparent conductive portion s30 c includes a second periphery s30 c 1surrounding the first periphery f30 c 1, and the third transparentconductive portion t30 c includes a third periphery t30 c 1 surroundedby the first periphery f30 c 1 in the top view.

As shown in FIGS. 6D and 7 , the reflective layer 40 c formed on thefirst transparent conductive portion f30 c. The reflective layer 40 cincludes a second outer edge 401 c and a second inner edge 402 csurrounded by the second outer edge 401 c. The reflective layer 40 cneither outwardly extends to exceed the first outer edge 301 c and/orthe first inner edge 302 c of the transparent conductive layer 30 c noroutwardly extends to exceed the first edge E1 and/or the second edge E2of the semiconductor structure 1000 c. In the present embodiment, thesecond outer edge 401 c is substantially aligned to the first outer edge301 c, and the second inner edge 402 c is substantially aligned to thefirst inner edge 302 c. As shown in FIGS. 6E and 7 , the secondinsulating structure 50 c is formed on the reflective layer 40 c, andcovers the first insulating structure 20 c. In one embodiment, thesecond insulating structure 50 c including the plurality of protrusions5031 c and the plurality of recesses 5032 c as shown in FIG. 6E′ arelocated on the exposed part of the semiconductor structure 1000 c andcovers the first surface 1011 c or the transparent conductive layer 30 cshown in FIGS. 6C and 6C′. More specifically, the plurality ofprotrusions 5031 c and the plurality of recesses 5032 c are arrangedalternately along the first surface 1011 c, and discontinuously coversthe first surface 1011 c. More specifically, the plurality ofprotrusions 5031 c covers portions of the first surface 1011 c which iscovered by the plurality of protrusions 2011 c, and the plurality ofrecesses 5032 c exposes portions of the first surface 1011 c which isexposed by the plurality of recesses 2012 c. In one embodiment, theplurality of protrusions 5031 c covers portions of the secondtransparent conductive portion s30 c and the plurality of recesses 5032c exposes portions of the second transparent conductive portion s30 c.

Please refer to FIG. 6G, similar to the light-emitting device 1 c, thelight-emitting device 2 c includes the contact layer 60 c having thefirst contact part 601 c, the second contact part 602 c and the pinregion 600 c. The first contact part 601 c electrically connects to thefirst semiconductor layer 101 c through the first adhesion opening 511c, the first insulating openings 501 c and the second transparentconductive portion s30 c disposed on the first surface 1011 c and thethird transparent conductive portion t30 c disposed on the secondsurface 1012 c in the vias 100 c. On the other hand, the second contactpart 602 c electrically connects to the second semiconductor layer 102 cthrough the second adhesion openings 512 c, and the second insulatingopenings 502 c, the reflective layer 40 c and the first transparentconductive portion f30 c disposed on the surface 102 s of the secondsemiconductor layer 102 c. In one embodiment, the material of the firstcontact part 601 c and the second contact part 602 c are the same andboth of them are multi-layer structure.

In one embodiment, the first contact part 601 c includes a first portionand the second portion covered the first portion. The material of thefirst portion includes Ag/NiTi/TiW/Pt and the material of the secondportion includes Ti/Al/Ti/Al/Cr/Pt sequentially formed on thesemiconductor structure 1000 c in a direction from the semiconductorstack 10 c to the second pad 90 c. In the embodiment, the second contactpart 602 c also includes a first portion and a second portion similarwith the first contact part 601 c. The material of the first portion andthe second portion of the second contact part 602 c can be the same withthat of the first contact part 601 c. In one embodiment, the reflectivestructure and the first contact part 601 c include a same material withhigh reflectivity. The reflective structure and the second contact part602 c include a same material with high reflectivity. In one embodiment,the reflective structure, the first contact part 601 c, and the secondcontact part 602 c include silver.

In one embodiment, the light-emitting device 2 c includes the secondtransparent conductive portion s20 c and the third transparentconductive portion t30 c between the contact layer 60 c and the firstsemiconductor layer 101 c, both of the first contact part 601 c and thesecond contact part 602 c including silver, and the adhesion layer 51 cbetween the contact layer 60 c and the second insulating structure 50 c.Comparing with the light-emitting device 2 c, the conventionallight-emitting device is similar to the Sample C mentioned above andincludes a first contact part without silver. For example, the materialof the first contact part of the conventional light-emitting deviceincludes Cr/Al/Cr/Al/Cr/Pt sequentially formed on a semiconductorstructure 1000 c. The light-emitting device 2 c in the presentembodiment has higher brightness caused by the first contact part 601 cwith silver to increase the reflective area of the light-emitting device2 c, and thus the brightness of the light-emitting device 2 c could beenhanced. The brightness (I_(V2)) of the conventional light-emittingdevice is 923.75 mW and the brightness (I_(V2)) of the light-emittingdevice 2 c in the embodiment is 965.83 mW. Therefore, the brightness ofthe light-emitting device 2 c in the embodiment is increased by 4.56%higher than the conventional light-emitting device.

FIG. 8 is a schematic view of a light-emitting apparatus 3 in accordancewith an embodiment of the present application. The light-emitting devicecan be selected from the foregoing embodiments, and is mounted on thefirst spacer 511 and the second spacer 512 of the package substrate 51in the form of flip chip. The first spacer 511 and the second spacer 512are electrically insulated from each other by an insulating portion 53including an insulating material. The main light-extraction surface ofthe flip-chip is one side of the growth substrates opposite to thepad-forming surface. A reflective structure 54 can be provided aroundthe light-emitting device to increase the light extraction efficiency ofthe light-emitting apparatus 3.

FIG. 9 illustrates a structure diagram of a light-emitting apparatus 4in accordance with an embodiment of the present application. A lightbulb includes an envelope 602, a lens 604, a light-emitting module 610,a base 612, a heat sink 614, a connector 616 and an electricalconnecting device 618. The light-emitting module 610 includes a submount606 and a plurality of light-emitting devices 608 on the submount 606,wherein the plurality of light-emitting devices 608 can be thelight-emitting devices or the light-emitting apparatus 3 described inabove embodiments.

The principle and the efficiency of the present application illustratedby the embodiments above are not the limitation of the application. Anyperson having ordinary skill in the art can modify or change theaforementioned embodiments. Therefore, the protection range of therights in the application will be listed as the following claims.

What is claimed is:
 1. A light-emitting device, comprising: asemiconductor structure comprising a first semiconductor layer, a secondsemiconductor layer on the first semiconductor layer, and an activelayer between the first semiconductor layer and the second semiconductorlayer, wherein the second semiconductor layer comprises a first edge; anexposed part exposing a first surface of the first semiconductor layerand surrounding the active layer and the second semiconductor layer,wherein the semiconductor structures comprises a first outside wall anda second outside wall, one end of the first surface connects the firstoutside wall, another end of the first surface connects the secondoutside wall, and the first edge is intersected by the second outsidewall and a surface of the second semiconductor layer; a first insulatingstructure comprising a top portion on the second semiconductor layer, aside portion on the second outside wall, and a bottom portion on thefirst semiconductor layer; a transparent conductive layer formed on thesurface of the second semiconductor layer; and a reflective structurelocated on the transparent conductive layer, wherein the reflectivestructure comprises a reflective layer, a barrier layer on thereflective layer, a DBR structure below the reflective layer, and aconnecting layer between the DBR structure and the reflective layer. 2.The light-emitting device of claim 1, wherein the reflective layercomprises an outer edge, and a distance between the first edge and theouter edge is greater than 0 μm and less than 10 μm.
 3. Thelight-emitting device of claim 2, wherein the distance is between 2 μmand 8 μm.
 4. The light-emitting device of claim 1, wherein thetransparent conductive layer comprises indium tin oxide (ITO), indiumzinc oxide (IZO), indium oxide (InO), tin oxide (SnO), cadmium tin oxide(CTO), antimony tin oxide (ATO), aluminum zinc oxide (AZO), zinc tinoxide (ZTO), gallium doped zinc oxide (GZO), tungsten doped indium oxide(IWO) or zinc oxide (ZnO).
 5. The light-emitting device of claim 1,wherein the connecting layer comprises indium tin oxide (ITO) or indiumzinc oxide (IZO).
 6. The light-emitting device of claim 1, furthercomprising a second insulating structure formed on the semiconductorstructure and the reflective structure, wherein the second insulatingstructure comprise an insulating opening on the reflective structure,and a plurality of protrusions and a plurality of recesses arrangedalternately along the first surface to discontinuously expose the firstsurface.
 7. The light-emitting device of claim 6, wherein the secondinsulating structure comprises a distributed Bragg reflector (DBR). 8.The light-emitting device of claim 6, further comprising a first contactpart formed on the first surface, and a second contact part form on theinsulating opening of the second insulating structure.
 9. Thelight-emitting device of claim 8, wherein the reflective structure andthe first contact part comprises silver.
 10. The light-emitting deviceof claim 9, further comprising an adhesion layer between the secondinsulating structure and the first contact layer.
 11. The light-emittingdevice of claim 10, wherein the adhesion layer comprises indium tinoxide (ITO), indium zinc oxide (IZO), indium oxide (InO), tin oxide(SnO), cadmium tin oxide (CTO), antimony tin oxide (ATO), aluminum zincoxide (AZO), zinc tin oxide (ZTO), gallium doped zinc oxide (GZO),tungsten doped indium oxide (IWO) or zinc oxide (ZnO).
 12. Thelight-emitting device of claim 8, wherein the first contact partcomprises a first periphery comprising a first periphery length largerthan a periphery length of the active layer in a top-view of thelight-emitting device.
 13. The light-emitting device of claim 8, whereinthe second contact part is surrounded by the first contact part in atop-view of the light-emitting device.
 14. The light-emitting device ofclaim 1, wherein the transparent conductive layer comprises a firstouter edge, the reflective layer comprises a second outer edge, and thefirst outer edge is closer to the first edge than the second outer edgeto the first edge.
 15. The light-emitting device of claim 1, wherein thetransparent conductive layer comprises a first outer edge, thereflective layer comprises a second outer edge, and the second outeredge is aligned to the first outer edge.
 16. The light-emitting deviceof claim 1, wherein the barrier layer comprises an outer edge surroundedby the reflective layer.
 17. The light-emitting device of claim 1,wherein the barrier layer comprises an outer edge aligned with an outeredge of the reflective layer.
 18. The light-emitting device of claim 1,further comprising a via passing through the second semiconductor layerand the active layer to expose the first semiconductor layer.
 19. Thelight-emitting device of claim 18, further comprising a third insulatingstructure located on the first contact part and the second contact part,and comprising a first opening on the first contact part and a secondopening on the second contact part.
 20. The light-emitting device ofclaim 19, wherein the third insulating structure comprises a DistributedBragg reflector (DBR).